\[\text{MSE} = \frac{1}{n} \sum_{i=1}^{n} (y_i - \hat{y}_i)^2\] abbreviation：
S - Strong signals
WC - Weak but correlated signals
WI - Weak but independent signals
FS - Forward selection
spe - specificity
sen - sensitivity
eg: ‘SLASSOspe’ stands for the specificity of selecting strong signals by LASSO.